中文摘要：

利用在长江口崇明岛获得的一个第四纪钻孔,对中更新世末以来的沉积物进行了OSL、14C测年,在此基础上进行岩性、微体古生物和孢粉分析,以探讨现代长江口形成的基础以及末次冰消期以来在气候-海平面波动控制下河口沉积环境的演变。研究结果显示,本孔所在地中更新世末处于湖沼环境,但晚更新世一直以河流环境为主,且主要发育末次冰期的河道滞留相沉积。在此基础上,随着末次冰消期海平面的上升,先后发育了河口湾和三角洲沉积体系。末次冰消期的海平面快速上升在本孔沉积物记录中体现为微体古生物化石较丰富,潮流作用显著。全新世早期长江口堆积速率明显高于全新世中晚期,应当反映了温暖湿润的季风气候条件下入海泥沙非常丰富。

英文摘要：

The present study measured OSL and 14C ages for late Quaternary sediments in a borehole drilled in the Chongming Island,Yangtze estuary.Lithology,microfossils,and sporopollen were further analyzed to discuss the formation of the modern Yangtze estuary and sedimentary environmental changes since the last deglaciation.The results indicate a lacustrine and marsh environment at the end of mid-Pleistocene.Fluvial facies dominates during late Pleistocene,especially gravel sediments of the riverbed prevailed during the last glaciation.With the sea level rise during the last deglaciation,estuarine and deltaic sedimentary systems developed successively in the study area.The rapid sea level rise during late deglaciation was demonstrated as rich marine microfossils and strong tidal intrusion in the present borehole sediments.Meanwhile,the high sedimentation rate indicates warm and humid monsoon climate and associated plentiful sediment discharge into the estuary during the early Holocene.